Audi RS3, 2018: Stopping, Turning, and Going

The 2018 Audi RS3 that I purchased from Flow Motors in Winston Salem has been put through several paces. From a bone-stock appearance at VIR at just under 1200 miles, to it’s first full season as a track-day work horse with 24,500 miles and just over a year of dutiful service. I wanted to take some time and point out the original strategy for this car, what it is inevitably meant to be, and the overall plan for getting it there.

I’ll break this down into 3 other separate posts below:

For those of you who don’t want a long read, and just want the parts list, here ya go:

First and foremost, this is an amazingly capable car straight from the factory. I simply wanted to accentuate it’s capabilities, and within 2 hours of effort, be able to convert from street to track (and back). This limits me to maintaining a level of comfort that my wife/customers/friends won’t complain about, and yet when I push the accelerator, I still get the “whoa….” factor. I run higher speed tracks (VIR, CMS), as well as technical low-speed tracks (CMP, Dominion), so a good balance is going to be key. I also rather like having a warranty on an expensive drive train, so every modification has been blessed by my Audi Service Advisor, with the understanding of what parts I’d end up voiding, and what my actual risk was (ie: I changed the springs… so there’s no warranty on, well, the springs…!)

Tires: Audi designed this car with the knowledge that the additional cylinder, oil coolers, and other accessories to support the 2.5L 5 cyl would create some additional understeer (ie: the car will tend to go straight instead of rotate into the corner). They chose to compensate for this by running wider wheels and tires on the front of the car compared the rear (Front: 19×8.5 with Pirelli P-Zero 255/30; Rear: 19×8 235/35). Yes, you read that right – It’s wider on the front than the rear. The stock Pzeros are designed to be a bit narrower than some of the competing counter parts, and simply start screaming at you when they build even the smallest amount of heat. For street use, they are a wonderful tire, and need no heat to excel at that type of level. That said, they still are a pure-summer tire, so at temps under 40, you really should be running an all-season, or a dedicated winter tire depending on your climate.

Brakes: So. This car comes with the same front brakes that Lamborghini puts on their Gallardo, which is the same that come on the B8 RS4/RS5. This is a truly great (but heavy) Brembo caliper. So – Why is this a problem? Because there is simply zero airflow. If you look at the front of the car (picture below) – the intercooler and radiator are in the center, and there are oil coolers on each side… So you can get some limited air from the bottom… and that’s pretty much it. I’ve now had two (out of 10) days on track where my brake fluid (Castrol SRF) did not boil. And if you weren’t aware, that’s not good. The secondary issue is that while upgrading the front rotors, they did not change the rears from the factory Audi S3 size… so it created a bit of a brake imbalance. This results in the rear of the car wanting to become a bit unsettled in high speed/hard braking. Update: Fixed most of this by using small Ryobi battery powered fans as soon as I pit!

The plan forms:

With the above information in mind, I reached out to Michelin, who had just released the Michelin Pilot Sport 4S, and as I wasn’t planning to replace my wheels, it just worked out to be in my correct sizes front and rear. If you’ve never driven on it, just accept that it’s about one notch away from the traction you get from the R-comp of a generation ago, which is astounding (And you can drive them to and from the track… which is a massive thing for a weekend warrior with no trailer or easy way to get tires to the track!)

Next, I reached out to Ken from KNSbrakes, who recommended two things – rotors and pads. The pad recommendation was for CarboTech XP12 front, and XP10 rear. They are extremely rotor friendly, and the support system from the team at CarboTech has been nothing short of phenomenal. It doesn’t hurt that Ken is local to me in Raleigh, NC, and CarboTech’s team is local-ish in Charlotte. The next piece Ken recommended was Girodisc rotors. Anybody who has done any high performance track work has heard of Girodisc, and the reputation speaks for itself. Moving to a directional rotor vein, and a slotted rotor instead of drilled has made a difference in my confidence under braking, and the two times I’ve not boiled fluid was after running this pad/rotor setup for the track.

Results:

The above setup is solid, and a minimal initial investment to get the capabilities of the car a step above where it came from the factory, both from a reliability and safety factor. That said, in the RS3 community, once you change the tires, you stop running out of any excuse other than “the driver” pretty quickly!

The next steps:

Next up is a bit of a mixed bag. I knew I wanted to improve the handling to match the capabilities of the new tires, and I wanted the engine to breathe a bit better. As this is still a street car, removing chassis slop was also something I wanted to take into consideration, therefore making the car more predictable and relying more on the suspension to do the job as opposed to the chassis flex having major impacts to the handling. In the next few posts, I’ll talk about how to stop, including a few theories and links to why this car does what it does; how to turn it properly; and how to get a bit more out of the engine.